Annular-jet turbine



Jan. 11,1927. 3,971

H. B ,TAYLOR' ANNULAR JET TURBINE Original Filed June 16, 1921 Patented Jan. 11, 1921.

, UNITED STATES 1,613,971 PATENT OFFICE.

HARVEY IBIRCEARD TbjYLoR, O]? PHILADELPHIA PENNSYLVANIA.

ANnULAR-JET TURBINE.

Original application filed June 16, 1921, Serial No. 447,891. Divided and this application filed February This invention relates to hydraulic turbines and particularly to turbines of the impulse type. The object of the invention is to provide such a turbine in which the jet I. will be of generally annular form so as to I continuously'act on all the runner buckets and to provide'buckets for receiving the jet and efliciently guiding the stream lines so as to reduce frictional resistance.

Further objects of the invention particularly in the simple symmetrical formation of the buckets will appear from the following description taken in connection with the accompanying drawings, in which Fig. 1 is a vertical sectional view of a turbine lllustrating the invention.

' Fig. 2 is a sectional detail view on line 2-2 of Figs. 1 and 3.

Fig.. 3 is a sectional detail view on line 3 -3 of Fig. 1. i

,Fig. 4 is a section similar to Fig. 2 but illustrating a modification.

Fig. 5 is a view similar to Fig. 1, but illustrating a modified form of turbine, and Fig. 6 is a fragmentary sectional horizontal view showing the guide vanes taken on the line 6- 6 of Fig. 5.

. In the embodiment of the invention shown in Fi s. 1 to 3 the jet J passes downward out o annular orifice 12, the amount'of the flow being controlled by varying the thickness of the jet by adjusting the position of the annular wedge 18 in orifice 12. The runner R comprises buckets 14 mounted on a central hub 15 on shaft 16. The hub 15 is cylindrical and the surfaces of the buckets curveinto and merge with the cylindrical outer surface of this hub which is continuous bet-ween the buckets. The buckets 14 are cup 40 shaped curving backward from the entrance edge 17, as shown in Fig. 2, which is a cross section as cut by a central cylindrical surface. and also curving backward from the vertical center on each side as indicated in Fig. 3 which shows a cross-section cut by. a plane surface perpendicular to the axis of the turbine. A continuous shroud rin or band could be used to connect the buc ets, but this would only be employed for mechanical reasons and toreduce windage, and

would not have any hydraulic function, as it would not be in conatct with the water. It will, in many cases, be preferable to omit a continuous band and to form each bucket 14 separately as shown, and when desired the Serial No. 8,368.

buckets can be cast separately and bolted or otherwise attached to the hub. By the use of such cup shaped buckets, the water stream entering each bucket can be kept together so as to occupy a minimum volume, and have both its bucket surface and air surface reduced in order to keep the surface friction to the least possible value. The curved form of the bucket in a section normal to the flow, such as Fig. 3, prevents undue spreading of the water stream. If the stream is permitted to spread out it becomes an excessively thin sheet with consequent tendeny toward roughening of the surfaces and spraying. The curvature of the buckets transverse to the flow prevents this and tends to keep the water in a compact mass. At the same time,, the bucket 14 has small dimensions and therefore does not create excessive windage. The discharge edges of the buckets are so proportioned that the discharged jet will just escape contact with the back 21 of the next succeeding bucket. The inflow edge 17 of the bucket as shown in Fig. 2 will be given an angle suitable to the relative direction of entrance of the jet with respect to the wheel.

- The bucket shown in Figs. 1 to 3 is suitable for a moderate specific speed, the speed, however, being much, higher than that. of impulse turbines of the usual tangential type. If still higher specific speeds are deentrance edges 17 inclined forward, the dis-' charge from the buckets being diagonally backward so as to clear the rear surfaces 21' of the following buckets.

In Fig. 5 the jet J curves from radial to axial at its base and the thickness of the jet is controlled by the axially movable plunger 25 while an inclined direction or whirl. may be imparted to it by the stay and guide vanes 26. The runner R has'its hub conical at its peripheral surface 27' and the buckets 28 are cup shaped somewhat as in Figs. 1 to 3, but having their inner surfaces curving into and merging with this conical surface 27. The buckets 28 have a diagonal inward direction of discharge at the inner edges and a diagonal outward dischar e at the outer edges thus differing from t e corresponding axial and radial discharge from the buckets 14 of Figs. 1 to 3. In the Fig. 1

form-the inner surface of the jet J is projected parallel to and in contact with the outer cylindrical surface of the hub 15 but in Fig. 5 the inner surface of the jet J does not contact with the conical surface 27 of the hub but leaves an intervening air space 30. Although in the embodiments shown the buckets are carried by a conical or cylin drical surface having straight line elements, these elements could be curved so that the buckets would merge with surfaces of revolution generated by a curved line.

As shown, the jet will spread so as to discharge in greatly diverging directions from till the bucket, it being possible with this cupshaped type of 'bucket to have the discharge extend through an angle approachlng almost 180, and this can be done without requiring a large extent of surface in contact with the jet.

I claim:

1. In an impulse turbine the combination with means for forming an annular axially directed jet, of a runner having buckets with jet receiving surfaces curved transversely to and in the direction of the stream lines of the jet.

2. In an impulse turbine the combination with means for forming an annular axially directed jet, of a runner having buckets with jet receiving surfaces curved transversely and rearwardly with respect to the stream lines of the jet.

, 3. In an impulse turbine the combination with means for forming an annular axially directed jet, of a runner having buckets with jet receiving surfaces curved transversely and rearwardly with respect to the stream lines of the jet on each side of said jet..

4;. In an impulse turbine the combination with means for forming an annular axially directed jet, of a runner having buckets with jet receiving surfaces curved transversely to the stream lines of the jet, each bucket being concaved and having the entrance ortion thereof extending upwardly and being inclined in the direction of runner rotation so that the entrance edge leads the remainder of the bucket.

5. In an impulse turbine the combination with means for forming an annular axially directed jet, of a runner havin buckets with jet receiving surfaces curved transversely with respect to the direction in which the stream lines enter the runner; and each of said surfaces at its entrance edge being inclined in the direction of motion of the runner so that the entrance edge leads the remainder of the surface. I

6. I11 an impulse turbine the combination with means for forming an annular axially directed jet, of a runner havin buckets with jet receiving surfaces curved transversely with respect to the direction in which the stream lines enter the runner; and each of said surfaces at its entrance edge being inclined so that the entrance edge leads the and means forming an inlet passage havi g an annular orifice for directing an axially progressing continuous circular JCI/ against all of said buckets simultaneously, the runner buckets having jet receiving surfaces curved transverselv to the stream lines of the jet.

9. An impulse. turbine having a runner provided with a circular series of buckets and means forming an inlet passage having an annular orifice for directing an axially progressing continuous circular jet against -all of sa d buckets simultaneously, the runner buckets having. jet receiving surfaces curved transversely to the stream lines of the jet on each side of the jet.

10. An impulse turbine provided with a runner. and an inlet casing having a jet forming orifice around the runner shaft adapted to form an axially progressing annular jet and to direct the jet against the runner and means co-operating. with said .orifice for controlling the flow of liquid therethrough, the runner buckets having jet receiving surfaces curved transversely to the stream hnes of the jet.

11. In an impulse turbine-the combination with a runner, of an inlet casing having a jet forming orifice around the runner shaft adapted to form an axially progressing annular jet and to direct the et against said runner, and an annular plunger controlling the flow through said orifice, the runner buckets having-jet receiving surfaces curved transversely to the stream lines of the jet.

12. An impulse turbine having meansfor formin an axially progressing circular jet containlng tangential components of motion and arunner having a circular series of buckets continuously acted upon by said jet, the runner buckets having jet receiving surfaces curved transversely to the stream lines of the jet,

13. In an impulse turbine the combination with means for forming an axially progressing circular jet containing tangential components of motion of a runner having a circular series of buckets continuously acted upon by said jet and means for varying the thickness of said jet to control the speed of said runner, the runner buckets having jet receiving surfaces curved transversely to th stream lines of the jet. I

14. An impulse turbine having a runner provided with a circular series of buckets, and means forming an inlet passage having an annular orifice for directing an axially progressing continuous circular jet against all of said buckets simultaneously, the runner buckets having jet receiving surfaces curved transversely and rearwardly with respect to the stream lines of the jet.

15. An impulse turbine having a runner provided with a circular series of buckets, and means forming an inlet passage having an annular orifice for directlng an axially progressing continuous circular jet against all of said buckets simultaneously, the runner buckets having jet receiving surfaces curved transversely {to the stream lines of the jet and inclined in the direction of rotation so that the entrance edges lead the remainder of their respective surfaces.

16. In a hydrauhc impulse turbine of large capacity and high specific speed the combination with a vertical shaft Wheel having buckets thereon curved transversely to the stream lines of a jet, of means for forming a jet and directing it against said buckets from above, and varying the size of said jet while preserving its form.

17. Inahydrauhc im ulseturbineof large capacity and. high speclfic speed the combination with a vertical shaft wheel having buckets thereon curved transversely to the i stream lines of a jet and inclined forward in the direction of rotation, of means for forming a jet and directing it against said buckets from above, and varying the size'of said jet while preserving its form.

18. In an impulse turbine the combination with means for forming an annular axially directed jet, of a runner having buckets with jet receivingsurfaces curved transversely to the stream lines of the jet, the said jet receiving surface of each bucket having its entrance portion making an angle not greater than 90 with the direction of runner motion and being concavely curved to make a still smaller angle with the direction of runner motion at discharge.

19. In an impulse turbine of large capacity and high specific speed the combination with an axial flow runner having buckets adapted to receive a free jet on one side and pass it through and discharge it on the other side, said buckets curving transversely and increasing in transverse width from the inlet side to the outlet side, of jet forming means adapted to direct a free jet against I said buckets on the entrance side, and means for varying the cross sectional area of said jet.

20. In an impulse turbine the combination with a runner, of an entrance casing having an annular jet forming orifice adapted to direct a circular axially progressing jet against said runner. and guide vanes in said casing ad acent said orifice and adapted 'to impart to said jet tangential components of flow around the axis of the "runner, the runner buckets having et receiving surfaces curved transversely to the stream lines of the et.

HARVEY BIRGHARD TAYLOR. 

